I ran across This PSU, and found it very interesting.. 
100% Silent The picoPSU-120 mini PSU is a 100% silent dc to dc solution. No fans, no noise, just power for small and silent PCs.
picoPSU-120 is a fully compliant DC-DC ATX PSU. It can power VIA mini-ITX boards with C3 or C7 processors, P3, P4, Pentium-M, and AMD processors